A lot of other software packages have a
very simple method of providing security with a single linear
privilege control. With this method you may have say privileges 1
to 16 on your system. You place the required users in each
privilege level and they only have access to commands in that
level. This give you 16 unique security levels. Users who have used
these software packages then assume that Citect operates in the
same way and then ask why Citect only has 8 privilege levels.

With Citect security scheme you would normally only need 3
privileges levels, however we decided to provide 8 for any user
with unusual requirements. You only need 3 privilege levels because
the privileges are used in associated with the areas and you may
have up to 256 areas in your Citect project. This gives you a
matrix of security which is must more useable than a single linear
system. You should also note that a user may belong to more than
one privilege and more than 1 area. This gives a huge number of
security levels combinations. The total number of security levels
is 2 to the power of 256, times 2 to power of 8 which is a number
in the order of billions of billions.